Annotation of src/usr.bin/ssh/ssh.c, Revision 1.373
1.373 ! djm 1: /* $OpenBSD: ssh.c,v 1.372 2013/02/22 04:45:09 dtucker Exp $ */
1.1 deraadt 2: /*
1.32 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * Ssh client program. This program can be used to log into a remote machine.
7: * The software supports strong authentication, encryption, and forwarding
8: * of X11, TCP/IP, and authentication connections.
9: *
1.64 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
16: * Copyright (c) 1999 Niels Provos. All rights reserved.
1.202 markus 17: * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
1.64 deraadt 18: *
19: * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
20: * in Canada (German citizen).
21: *
22: * Redistribution and use in source and binary forms, with or without
23: * modification, are permitted provided that the following conditions
24: * are met:
25: * 1. Redistributions of source code must retain the above copyright
26: * notice, this list of conditions and the following disclaimer.
27: * 2. Redistributions in binary form must reproduce the above copyright
28: * notice, this list of conditions and the following disclaimer in the
29: * documentation and/or other materials provided with the distribution.
30: *
31: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
32: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
34: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
35: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
37: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
38: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
39: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
40: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.32 deraadt 41: */
1.1 deraadt 42:
1.293 deraadt 43: #include <sys/types.h>
1.312 djm 44: #include <sys/ioctl.h>
1.326 dtucker 45: #include <sys/param.h>
1.312 djm 46: #include <sys/queue.h>
1.259 stevesk 47: #include <sys/resource.h>
1.280 stevesk 48: #include <sys/socket.h>
1.264 stevesk 49: #include <sys/stat.h>
1.312 djm 50: #include <sys/types.h>
51: #include <sys/time.h>
1.352 djm 52: #include <sys/wait.h>
1.258 stevesk 53:
1.265 stevesk 54: #include <ctype.h>
1.285 stevesk 55: #include <errno.h>
1.281 stevesk 56: #include <fcntl.h>
1.286 stevesk 57: #include <netdb.h>
1.258 stevesk 58: #include <paths.h>
1.279 stevesk 59: #include <pwd.h>
1.263 stevesk 60: #include <signal.h>
1.287 stevesk 61: #include <stddef.h>
1.291 stevesk 62: #include <stdio.h>
1.290 stevesk 63: #include <stdlib.h>
1.289 stevesk 64: #include <string.h>
1.288 stevesk 65: #include <unistd.h>
1.49 markus 66:
67: #include <openssl/evp.h>
1.72 markus 68: #include <openssl/err.h>
1.1 deraadt 69:
1.293 deraadt 70: #include "xmalloc.h"
1.84 markus 71: #include "ssh.h"
72: #include "ssh1.h"
73: #include "ssh2.h"
1.341 djm 74: #include "canohost.h"
1.84 markus 75: #include "compat.h"
76: #include "cipher.h"
1.1 deraadt 77: #include "packet.h"
78: #include "buffer.h"
1.123 markus 79: #include "channels.h"
1.49 markus 80: #include "key.h"
1.58 markus 81: #include "authfd.h"
1.49 markus 82: #include "authfile.h"
1.83 markus 83: #include "pathnames.h"
1.214 djm 84: #include "dispatch.h"
1.81 markus 85: #include "clientloop.h"
1.84 markus 86: #include "log.h"
87: #include "readconf.h"
88: #include "sshconnect.h"
89: #include "misc.h"
1.95 markus 90: #include "kex.h"
91: #include "mac.h"
1.213 deraadt 92: #include "sshpty.h"
1.212 djm 93: #include "match.h"
1.214 djm 94: #include "msg.h"
1.225 dtucker 95: #include "uidswap.h"
1.327 andreas 96: #include "roaming.h"
1.278 stevesk 97: #include "version.h"
1.49 markus 98:
1.333 markus 99: #ifdef ENABLE_PKCS11
100: #include "ssh-pkcs11.h"
1.137 jakob 101: #endif
1.127 markus 102:
1.49 markus 103: extern char *__progname;
1.1 deraadt 104:
1.316 djm 105: /* Flag indicating whether debug mode is on. May be set on the command line. */
1.1 deraadt 106: int debug_flag = 0;
107:
1.359 djm 108: /* Flag indicating whether a tty should be requested */
1.1 deraadt 109: int tty_flag = 0;
110:
1.45 markus 111: /* don't exec a shell */
112: int no_shell_flag = 0;
113:
1.33 markus 114: /*
115: * Flag indicating that nothing should be read from stdin. This can be set
116: * on the command line.
117: */
1.1 deraadt 118: int stdin_null_flag = 0;
119:
1.33 markus 120: /*
1.344 djm 121: * Flag indicating that the current process should be backgrounded and
122: * a new slave launched in the foreground for ControlPersist.
123: */
124: int need_controlpersist_detach = 0;
125:
126: /* Copies of flags for ControlPersist foreground slave */
1.359 djm 127: int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
1.344 djm 128:
129: /*
1.33 markus 130: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 131: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 132: * background.
133: */
1.1 deraadt 134: int fork_after_authentication_flag = 0;
135:
1.331 dtucker 136: /* forward stdio to remote host and port */
137: char *stdio_forward_host = NULL;
138: int stdio_forward_port = 0;
139:
1.33 markus 140: /*
141: * General data structure for command line options and options configurable
142: * in configuration files. See readconf.h.
143: */
1.1 deraadt 144: Options options;
145:
1.139 markus 146: /* optional user configfile */
147: char *config = NULL;
148:
1.33 markus 149: /*
150: * Name of the host we are connecting to. This is the name given on the
151: * command line, or the HostName specified for the user-supplied name in a
152: * configuration file.
153: */
1.1 deraadt 154: char *host;
155:
1.22 provos 156: /* socket address the host resolves to */
1.37 markus 157: struct sockaddr_storage hostaddr;
1.1 deraadt 158:
1.112 markus 159: /* Private host keys. */
1.173 markus 160: Sensitive sensitive_data;
1.1 deraadt 161:
1.10 dugsong 162: /* Original real UID. */
163: uid_t original_real_uid;
1.177 markus 164: uid_t original_effective_uid;
1.1 deraadt 165:
1.45 markus 166: /* command to be executed */
167: Buffer command;
168:
1.85 djm 169: /* Should we execute a command or invoke a subsystem? */
170: int subsystem_flag = 0;
171:
1.170 markus 172: /* # of replies received for global requests */
1.315 djm 173: static int remote_forward_confirms_received = 0;
1.170 markus 174:
1.313 djm 175: /* mux.c */
176: extern int muxserver_sock;
177: extern u_int muxclient_command;
178:
1.186 djm 179:
1.1 deraadt 180: /* Prints a help message to the user. This function never returns. */
181:
1.126 itojun 182: static void
1.93 itojun 183: usage(void)
1.1 deraadt 184: {
1.208 markus 185: fprintf(stderr,
1.321 jmc 186: "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
1.251 jmc 187: " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
1.334 jmc 188: " [-I pkcs11] [-i identity_file]\n"
189: " [-L [bind_address:]port:host:hostport]\n"
1.232 djm 190: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
1.233 jmc 191: " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
1.331 dtucker 192: " [-W host:port] [-w local_tun[:remote_tun]]\n"
193: " [user@]hostname [command]\n"
1.208 markus 194: );
1.257 dtucker 195: exit(255);
1.1 deraadt 196: }
197:
1.126 itojun 198: static int ssh_session(void);
199: static int ssh_session2(void);
200: static void load_public_identity_files(void);
1.352 djm 201: static void main_sigchld_handler(int);
1.312 djm 202:
203: /* from muxclient.c */
204: void muxclient(const char *);
205: void muxserver_listen(void);
1.45 markus 206:
1.361 djm 207: /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
208: static void
209: tilde_expand_paths(char **paths, u_int num_paths)
210: {
211: u_int i;
212: char *cp;
213:
214: for (i = 0; i < num_paths; i++) {
215: cp = tilde_expand_filename(paths[i], original_real_uid);
216: xfree(paths[i]);
217: paths[i] = cp;
218: }
219: }
220:
1.32 deraadt 221: /*
222: * Main program for the ssh client.
223: */
1.2 provos 224: int
225: main(int ac, char **av)
1.1 deraadt 226: {
1.326 dtucker 227: int i, r, opt, exit_status, use_syslog;
1.356 djm 228: char *p, *cp, *line, *argv0, buf[MAXPATHLEN], *host_arg;
1.358 djm 229: char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
1.31 markus 230: struct stat st;
1.98 markus 231: struct passwd *pw;
1.303 djm 232: int dummy, timeout_ms;
1.144 stevesk 233: extern int optind, optreset;
234: extern char *optarg;
1.244 djm 235: struct servent *sp;
1.232 djm 236: Forward fwd;
1.250 djm 237:
238: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
239: sanitise_stdfd();
1.31 markus 240:
1.33 markus 241: /*
1.346 djm 242: * Discard other fds that are hanging around. These can cause problem
243: * with backgrounded ssh processes started by ControlPersist.
244: */
245: closefrom(STDERR_FILENO + 1);
246:
247: /*
1.33 markus 248: * Save the original real uid. It will be needed later (uid-swapping
249: * may clobber the real uid).
250: */
1.31 markus 251: original_real_uid = getuid();
252: original_effective_uid = geteuid();
253:
1.184 stevesk 254: /*
255: * Use uid-swapping to give up root privileges for the duration of
256: * option processing. We will re-instantiate the rights when we are
257: * ready to create the privileged port, and will permanently drop
258: * them when the port has been created (actually, when the connection
259: * has been made, as we may need to create the port several times).
260: */
261: PRIV_END;
262:
1.31 markus 263: /* If we are installed setuid root be careful to not drop core. */
264: if (original_real_uid != original_effective_uid) {
265: struct rlimit rlim;
266: rlim.rlim_cur = rlim.rlim_max = 0;
267: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
268: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 269: }
1.107 markus 270: /* Get user data. */
271: pw = getpwuid(original_real_uid);
272: if (!pw) {
1.191 itojun 273: logit("You don't exist, go away!");
1.257 dtucker 274: exit(255);
1.107 markus 275: }
276: /* Take a copy of the returned structure. */
277: pw = pwcopy(pw);
1.31 markus 278:
1.33 markus 279: /*
280: * Set our umask to something reasonable, as some files are created
281: * with the default umask. This will make them world-readable but
282: * writable only by the owner, which is ok for all files for which we
283: * don't set the modes explicitly.
284: */
1.31 markus 285: umask(022);
286:
1.316 djm 287: /*
288: * Initialize option structure to indicate that no values have been
289: * set.
290: */
1.31 markus 291: initialize_options(&options);
292:
293: /* Parse command-line arguments. */
294: host = NULL;
1.320 djm 295: use_syslog = 0;
1.325 markus 296: argv0 = av[0];
1.31 markus 297:
1.266 djm 298: again:
1.316 djm 299: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.331 dtucker 300: "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) {
1.31 markus 301: switch (opt) {
1.91 jakob 302: case '1':
303: options.protocol = SSH_PROTO_1;
304: break;
1.47 markus 305: case '2':
306: options.protocol = SSH_PROTO_2;
307: break;
1.37 markus 308: case '4':
1.196 djm 309: options.address_family = AF_INET;
1.37 markus 310: break;
311: case '6':
1.196 djm 312: options.address_family = AF_INET6;
1.37 markus 313: break;
1.31 markus 314: case 'n':
315: stdin_null_flag = 1;
316: break;
317: case 'f':
318: fork_after_authentication_flag = 1;
319: stdin_null_flag = 1;
320: break;
321: case 'x':
322: options.forward_x11 = 0;
323: break;
324: case 'X':
325: options.forward_x11 = 1;
326: break;
1.320 djm 327: case 'y':
328: use_syslog = 1;
329: break;
1.202 markus 330: case 'Y':
331: options.forward_x11 = 1;
332: options.forward_x11_trusted = 1;
333: break;
1.31 markus 334: case 'g':
335: options.gateway_ports = 1;
336: break;
1.229 djm 337: case 'O':
1.332 djm 338: if (stdio_forward_host != NULL)
339: fatal("Cannot specify multiplexing "
340: "command with -W");
341: else if (muxclient_command != 0)
342: fatal("Multiplexing command already specified");
1.229 djm 343: if (strcmp(optarg, "check") == 0)
1.312 djm 344: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 345: else if (strcmp(optarg, "forward") == 0)
346: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 347: else if (strcmp(optarg, "exit") == 0)
1.312 djm 348: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.357 djm 349: else if (strcmp(optarg, "stop") == 0)
350: muxclient_command = SSHMUX_COMMAND_STOP;
1.365 djm 351: else if (strcmp(optarg, "cancel") == 0)
352: muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
1.229 djm 353: else
354: fatal("Invalid multiplex command.");
355: break;
1.183 stevesk 356: case 'P': /* deprecated */
1.31 markus 357: options.use_privileged_port = 0;
358: break;
359: case 'a':
360: options.forward_agent = 0;
1.53 markus 361: break;
362: case 'A':
363: options.forward_agent = 1;
1.31 markus 364: break;
365: case 'k':
1.204 dtucker 366: options.gss_deleg_creds = 0;
1.297 djm 367: break;
368: case 'K':
369: options.gss_authentication = 1;
370: options.gss_deleg_creds = 1;
1.31 markus 371: break;
372: case 'i':
373: if (stat(optarg, &st) < 0) {
1.128 fgsch 374: fprintf(stderr, "Warning: Identity file %s "
1.231 otto 375: "not accessible: %s.\n", optarg,
376: strerror(errno));
1.31 markus 377: break;
378: }
1.371 dtucker 379: add_identity_file(&options, NULL, optarg, 1);
1.31 markus 380: break;
1.127 markus 381: case 'I':
1.333 markus 382: #ifdef ENABLE_PKCS11
383: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 384: #else
1.333 markus 385: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 386: #endif
1.127 markus 387: break;
1.31 markus 388: case 't':
1.359 djm 389: if (options.request_tty == REQUEST_TTY_YES)
390: options.request_tty = REQUEST_TTY_FORCE;
391: else
392: options.request_tty = REQUEST_TTY_YES;
1.31 markus 393: break;
394: case 'v':
1.197 markus 395: if (debug_flag == 0) {
1.66 markus 396: debug_flag = 1;
397: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 398: } else {
399: if (options.log_level < SYSLOG_LEVEL_DEBUG3)
400: options.log_level++;
1.66 markus 401: break;
1.197 markus 402: }
1.227 deraadt 403: /* FALLTHROUGH */
1.31 markus 404: case 'V':
1.209 markus 405: fprintf(stderr, "%s, %s\n",
406: SSH_VERSION, SSLeay_version(SSLEAY_VERSION));
1.31 markus 407: if (opt == 'V')
408: exit(0);
409: break;
1.255 reyk 410: case 'w':
1.256 reyk 411: if (options.tun_open == -1)
412: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 413: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 414: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 415: fprintf(stderr,
416: "Bad tun device '%s'\n", optarg);
1.257 dtucker 417: exit(255);
1.255 reyk 418: }
419: break;
1.331 dtucker 420: case 'W':
1.332 djm 421: if (stdio_forward_host != NULL)
422: fatal("stdio forward already specified");
423: if (muxclient_command != 0)
424: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 425: if (parse_forward(&fwd, optarg, 1, 0)) {
426: stdio_forward_host = fwd.listen_host;
427: stdio_forward_port = fwd.listen_port;
428: xfree(fwd.connect_host);
429: } else {
430: fprintf(stderr,
431: "Bad stdio forwarding specification '%s'\n",
432: optarg);
433: exit(255);
434: }
1.359 djm 435: options.request_tty = REQUEST_TTY_NO;
1.331 dtucker 436: no_shell_flag = 1;
437: options.clear_forwardings = 1;
438: options.exit_on_forward_failure = 1;
439: break;
1.31 markus 440: case 'q':
441: options.log_level = SYSLOG_LEVEL_QUIET;
442: break;
443: case 'e':
444: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 445: (u_char) optarg[1] >= 64 &&
446: (u_char) optarg[1] < 128)
1.78 markus 447: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 448: else if (strlen(optarg) == 1)
1.78 markus 449: options.escape_char = (u_char) optarg[0];
1.31 markus 450: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 451: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 452: else {
1.128 fgsch 453: fprintf(stderr, "Bad escape character '%s'.\n",
454: optarg);
1.257 dtucker 455: exit(255);
1.31 markus 456: }
457: break;
458: case 'c':
1.49 markus 459: if (ciphers_valid(optarg)) {
460: /* SSH2 only */
461: options.ciphers = xstrdup(optarg);
1.224 markus 462: options.cipher = SSH_CIPHER_INVALID;
1.49 markus 463: } else {
464: /* SSH1 only */
1.74 markus 465: options.cipher = cipher_number(optarg);
466: if (options.cipher == -1) {
1.128 fgsch 467: fprintf(stderr,
468: "Unknown cipher type '%s'\n",
469: optarg);
1.257 dtucker 470: exit(255);
1.49 markus 471: }
1.128 fgsch 472: if (options.cipher == SSH_CIPHER_3DES)
1.74 markus 473: options.ciphers = "3des-cbc";
1.128 fgsch 474: else if (options.cipher == SSH_CIPHER_BLOWFISH)
1.74 markus 475: options.ciphers = "blowfish-cbc";
1.128 fgsch 476: else
1.74 markus 477: options.ciphers = (char *)-1;
1.95 markus 478: }
479: break;
480: case 'm':
481: if (mac_valid(optarg))
482: options.macs = xstrdup(optarg);
483: else {
1.128 fgsch 484: fprintf(stderr, "Unknown mac type '%s'\n",
485: optarg);
1.257 dtucker 486: exit(255);
1.31 markus 487: }
488: break;
1.214 djm 489: case 'M':
1.242 djm 490: if (options.control_master == SSHCTL_MASTER_YES)
491: options.control_master = SSHCTL_MASTER_ASK;
492: else
493: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 494: break;
1.31 markus 495: case 'p':
1.113 stevesk 496: options.port = a2port(optarg);
1.323 djm 497: if (options.port <= 0) {
1.109 markus 498: fprintf(stderr, "Bad port '%s'\n", optarg);
1.257 dtucker 499: exit(255);
1.109 markus 500: }
1.31 markus 501: break;
502: case 'l':
503: options.user = optarg;
504: break;
1.141 stevesk 505:
506: case 'L':
1.324 djm 507: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 508: add_local_forward(&options, &fwd);
509: else {
1.128 fgsch 510: fprintf(stderr,
1.232 djm 511: "Bad local forwarding specification '%s'\n",
1.128 fgsch 512: optarg);
1.257 dtucker 513: exit(255);
1.31 markus 514: }
1.232 djm 515: break;
516:
517: case 'R':
1.324 djm 518: if (parse_forward(&fwd, optarg, 0, 1)) {
1.232 djm 519: add_remote_forward(&options, &fwd);
520: } else {
1.128 fgsch 521: fprintf(stderr,
1.232 djm 522: "Bad remote forwarding specification "
523: "'%s'\n", optarg);
1.257 dtucker 524: exit(255);
1.31 markus 525: }
526: break;
1.108 markus 527:
528: case 'D':
1.324 djm 529: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 530: add_local_forward(&options, &fwd);
1.232 djm 531: } else {
1.322 stevesk 532: fprintf(stderr,
533: "Bad dynamic forwarding specification "
534: "'%s'\n", optarg);
1.257 dtucker 535: exit(255);
1.109 markus 536: }
1.108 markus 537: break;
538:
1.31 markus 539: case 'C':
540: options.compression = 1;
541: break;
1.45 markus 542: case 'N':
543: no_shell_flag = 1;
1.359 djm 544: options.request_tty = REQUEST_TTY_NO;
1.45 markus 545: break;
546: case 'T':
1.359 djm 547: options.request_tty = REQUEST_TTY_NO;
1.45 markus 548: break;
1.31 markus 549: case 'o':
550: dummy = 1;
1.205 markus 551: line = xstrdup(optarg);
1.128 fgsch 552: if (process_config_line(&options, host ? host : "",
1.372 dtucker 553: line, "command-line", 0, &dummy, SSHCONF_USERCONF)
554: != 0)
1.257 dtucker 555: exit(255);
1.205 markus 556: xfree(line);
1.31 markus 557: break;
1.85 djm 558: case 's':
559: subsystem_flag = 1;
1.117 markus 560: break;
1.214 djm 561: case 'S':
562: if (options.control_path != NULL)
563: free(options.control_path);
564: options.control_path = xstrdup(optarg);
565: break;
1.117 markus 566: case 'b':
567: options.bind_address = optarg;
1.85 djm 568: break;
1.139 markus 569: case 'F':
570: config = optarg;
571: break;
1.31 markus 572: default:
573: usage();
1.1 deraadt 574: }
1.31 markus 575: }
576:
1.128 fgsch 577: ac -= optind;
578: av += optind;
579:
1.329 guenther 580: if (ac > 0 && !host) {
1.188 markus 581: if (strrchr(*av, '@')) {
1.128 fgsch 582: p = xstrdup(*av);
1.188 markus 583: cp = strrchr(p, '@');
1.128 fgsch 584: if (cp == NULL || cp == p)
585: usage();
586: options.user = p;
587: *cp = '\0';
588: host = ++cp;
589: } else
590: host = *av;
1.189 millert 591: if (ac > 1) {
592: optind = optreset = 1;
1.128 fgsch 593: goto again;
594: }
1.189 millert 595: ac--, av++;
1.128 fgsch 596: }
597:
1.31 markus 598: /* Check that we got a host name. */
599: if (!host)
600: usage();
601:
1.350 djm 602: OpenSSL_add_all_algorithms();
1.72 markus 603: ERR_load_crypto_strings();
1.31 markus 604:
605: /* Initialize the command to execute on remote host. */
606: buffer_init(&command);
1.1 deraadt 607:
1.33 markus 608: /*
609: * Save the command to execute on the remote host in a buffer. There
610: * is no limit on the length of the command, except by the maximum
611: * packet size. Also sets the tty flag if there is no command.
612: */
1.128 fgsch 613: if (!ac) {
1.31 markus 614: /* No command specified - execute shell on a tty. */
1.85 djm 615: if (subsystem_flag) {
1.128 fgsch 616: fprintf(stderr,
617: "You must specify a subsystem to invoke.\n");
1.85 djm 618: usage();
619: }
1.31 markus 620: } else {
1.128 fgsch 621: /* A command has been specified. Store it into the buffer. */
622: for (i = 0; i < ac; i++) {
623: if (i)
1.31 markus 624: buffer_append(&command, " ", 1);
625: buffer_append(&command, av[i], strlen(av[i]));
626: }
627: }
628:
629: /* Cannot fork to background if no command. */
1.316 djm 630: if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
631: !no_shell_flag)
632: fatal("Cannot fork into background without a command "
633: "to execute.");
1.31 markus 634:
1.101 markus 635: /*
636: * Initialize "log" output. Since we are the client all output
637: * actually goes to stderr.
638: */
1.325 markus 639: log_init(argv0,
1.316 djm 640: options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
1.320 djm 641: SYSLOG_FACILITY_USER, !use_syslog);
1.31 markus 642:
1.139 markus 643: /*
644: * Read per-user configuration file. Ignore the system wide config
645: * file if the user specifies a config file on the command line.
646: */
647: if (config != NULL) {
1.372 dtucker 648: if (!read_config_file(config, host, &options, SSHCONF_USERCONF))
1.142 stevesk 649: fatal("Can't open user config file %.100s: "
650: "%.100s", config, strerror(errno));
1.295 stevesk 651: } else {
1.326 dtucker 652: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
1.139 markus 653: _PATH_SSH_USER_CONFFILE);
1.326 dtucker 654: if (r > 0 && (size_t)r < sizeof(buf))
1.372 dtucker 655: (void)read_config_file(buf, host, &options,
656: SSHCONF_CHECKPERM|SSHCONF_USERCONF);
1.139 markus 657:
1.364 djm 658: /* Read systemwide configuration file after user config. */
1.223 deraadt 659: (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
1.210 djm 660: &options, 0);
1.139 markus 661: }
1.31 markus 662:
663: /* Fill configuration defaults. */
664: fill_default_options(&options);
665:
1.196 djm 666: channel_set_af(options.address_family);
667:
1.31 markus 668: /* reinit */
1.325 markus 669: log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
1.370 djm 670:
671: if (options.request_tty == REQUEST_TTY_YES ||
672: options.request_tty == REQUEST_TTY_FORCE)
673: tty_flag = 1;
674:
675: /* Allocate a tty by default if no command specified. */
676: if (buffer_len(&command) == 0)
677: tty_flag = options.request_tty != REQUEST_TTY_NO;
678:
679: /* Force no tty */
680: if (options.request_tty == REQUEST_TTY_NO || muxclient_command != 0)
681: tty_flag = 0;
682: /* Do not allocate a tty if stdin is not a tty. */
683: if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
684: options.request_tty != REQUEST_TTY_FORCE) {
685: if (tty_flag)
686: logit("Pseudo-terminal will not be allocated because "
687: "stdin is not a terminal.");
688: tty_flag = 0;
689: }
1.31 markus 690:
691: if (options.user == NULL)
692: options.user = xstrdup(pw->pw_name);
693:
1.317 dtucker 694: /* Get default port if port has not been set. */
695: if (options.port == 0) {
696: sp = getservbyname(SSH_SERVICE_NAME, "tcp");
697: options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
698: }
699:
1.356 djm 700: /* preserve host name given on command line for %n expansion */
701: host_arg = host;
1.343 djm 702: if (options.hostname != NULL) {
703: host = percent_expand(options.hostname,
704: "h", host, (char *)NULL);
705: }
706:
1.358 djm 707: if (gethostname(thishost, sizeof(thishost)) == -1)
708: fatal("gethostname: %s", strerror(errno));
709: strlcpy(shorthost, thishost, sizeof(shorthost));
710: shorthost[strcspn(thishost, ".")] = '\0';
711: snprintf(portstr, sizeof(portstr), "%d", options.port);
712:
1.317 dtucker 713: if (options.local_command != NULL) {
714: debug3("expanding LocalCommand: %s", options.local_command);
715: cp = options.local_command;
716: options.local_command = percent_expand(cp, "d", pw->pw_dir,
1.356 djm 717: "h", host, "l", thishost, "n", host_arg, "r", options.user,
1.358 djm 718: "p", portstr, "u", pw->pw_name, "L", shorthost,
719: (char *)NULL);
1.317 dtucker 720: debug3("expanded LocalCommand: %s", options.local_command);
721: xfree(cp);
722: }
1.195 markus 723:
724: /* force lowercase for hostkey matching */
725: if (options.host_key_alias != NULL) {
726: for (p = options.host_key_alias; *p; p++)
727: if (isupper(*p))
1.271 deraadt 728: *p = (char)tolower(*p);
1.246 djm 729: }
730:
1.190 markus 731: if (options.proxy_command != NULL &&
1.304 dtucker 732: strcmp(options.proxy_command, "none") == 0) {
733: xfree(options.proxy_command);
1.190 markus 734: options.proxy_command = NULL;
1.304 dtucker 735: }
1.245 djm 736: if (options.control_path != NULL &&
1.304 dtucker 737: strcmp(options.control_path, "none") == 0) {
738: xfree(options.control_path);
1.245 djm 739: options.control_path = NULL;
1.304 dtucker 740: }
1.31 markus 741:
1.214 djm 742: if (options.control_path != NULL) {
1.241 djm 743: cp = tilde_expand_filename(options.control_path,
744: original_real_uid);
1.304 dtucker 745: xfree(options.control_path);
1.358 djm 746: options.control_path = percent_expand(cp, "h", host,
747: "l", thishost, "n", host_arg, "r", options.user,
748: "p", portstr, "u", pw->pw_name, "L", shorthost,
749: (char *)NULL);
1.241 djm 750: xfree(cp);
1.214 djm 751: }
1.312 djm 752: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 753: fatal("No ControlPath specified for \"-O\" command");
1.242 djm 754: if (options.control_path != NULL)
1.312 djm 755: muxclient(options.control_path);
1.214 djm 756:
1.303 djm 757: timeout_ms = options.connection_timeout * 1000;
758:
1.77 markus 759: /* Open a connection to the remote host. */
1.203 djm 760: if (ssh_connect(host, &hostaddr, options.port,
1.303 djm 761: options.address_family, options.connection_attempts, &timeout_ms,
762: options.tcp_keep_alive,
1.177 markus 763: original_effective_uid == 0 && options.use_privileged_port,
1.179 markus 764: options.proxy_command) != 0)
1.257 dtucker 765: exit(255);
1.31 markus 766:
1.303 djm 767: if (timeout_ms > 0)
768: debug3("timeout: %d ms remain after connect", timeout_ms);
769:
1.33 markus 770: /*
771: * If we successfully made the connection, load the host private key
772: * in case we will need it later for combined rsa-rhosts
773: * authentication. This must be done before releasing extra
774: * privileges, because the file is only readable by root.
1.174 markus 775: * If we cannot access the private keys, load the public keys
776: * instead and try to execute the ssh-keysign helper instead.
1.33 markus 777: */
1.112 markus 778: sensitive_data.nkeys = 0;
779: sensitive_data.keys = NULL;
1.173 markus 780: sensitive_data.external_keysign = 0;
1.178 markus 781: if (options.rhosts_rsa_authentication ||
782: options.hostbased_authentication) {
1.349 djm 783: sensitive_data.nkeys = 7;
1.274 deraadt 784: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.180 deraadt 785: sizeof(Key));
1.177 markus 786:
787: PRIV_START;
1.112 markus 788: sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
1.276 dtucker 789: _PATH_HOST_KEY_FILE, "", NULL, NULL);
1.345 djm 790: sensitive_data.keys[1] = key_load_private_cert(KEY_DSA,
791: _PATH_HOST_DSA_KEY_FILE, "", NULL);
1.349 djm 792: sensitive_data.keys[2] = key_load_private_cert(KEY_ECDSA,
793: _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
794: sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
1.345 djm 795: _PATH_HOST_RSA_KEY_FILE, "", NULL);
1.349 djm 796: sensitive_data.keys[4] = key_load_private_type(KEY_DSA,
1.276 dtucker 797: _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1.349 djm 798: sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
799: _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
800: sensitive_data.keys[6] = key_load_private_type(KEY_RSA,
1.276 dtucker 801: _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1.177 markus 802: PRIV_END;
1.173 markus 803:
1.181 markus 804: if (options.hostbased_authentication == 1 &&
805: sensitive_data.keys[0] == NULL &&
1.349 djm 806: sensitive_data.keys[4] == NULL &&
807: sensitive_data.keys[5] == NULL &&
808: sensitive_data.keys[6] == NULL) {
1.345 djm 809: sensitive_data.keys[1] = key_load_cert(
810: _PATH_HOST_DSA_KEY_FILE);
811: sensitive_data.keys[2] = key_load_cert(
1.349 djm 812: _PATH_HOST_ECDSA_KEY_FILE);
813: sensitive_data.keys[3] = key_load_cert(
1.345 djm 814: _PATH_HOST_RSA_KEY_FILE);
1.349 djm 815: sensitive_data.keys[4] = key_load_public(
1.173 markus 816: _PATH_HOST_DSA_KEY_FILE, NULL);
1.349 djm 817: sensitive_data.keys[5] = key_load_public(
818: _PATH_HOST_ECDSA_KEY_FILE, NULL);
819: sensitive_data.keys[6] = key_load_public(
1.173 markus 820: _PATH_HOST_RSA_KEY_FILE, NULL);
821: sensitive_data.external_keysign = 1;
822: }
1.31 markus 823: }
1.33 markus 824: /*
825: * Get rid of any extra privileges that we may have. We will no
826: * longer need them. Also, extra privileges could make it very hard
827: * to read identity files and other non-world-readable files from the
828: * user's home directory if it happens to be on a NFS volume where
829: * root is mapped to nobody.
830: */
1.225 dtucker 831: if (original_effective_uid == 0) {
832: PRIV_START;
833: permanently_set_uid(pw);
834: }
1.31 markus 835:
1.33 markus 836: /*
837: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 838: * directory if it doesn't already exist.
1.33 markus 839: */
1.367 djm 840: if (config == NULL) {
841: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
842: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
843: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
844: if (mkdir(buf, 0700) < 0)
845: error("Could not create directory '%.200s'.",
846: buf);
847: }
1.31 markus 848:
1.104 markus 849: /* load options.identity_files */
850: load_public_identity_files();
851:
852: /* Expand ~ in known host file names. */
1.361 djm 853: tilde_expand_paths(options.system_hostfiles,
854: options.num_system_hostfiles);
855: tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1.149 markus 856:
857: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.352 djm 858: signal(SIGCHLD, main_sigchld_handler);
1.31 markus 859:
1.316 djm 860: /* Log into the remote system. Never returns if the login fails. */
1.303 djm 861: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
1.355 djm 862: options.port, pw, timeout_ms);
1.339 djm 863:
864: if (packet_connection_is_on_socket()) {
865: verbose("Authenticated to %s ([%s]:%d).", host,
866: get_remote_ipaddr(), get_remote_port());
867: } else {
868: verbose("Authenticated to %s (via proxy).", host);
869: }
1.31 markus 870:
1.112 markus 871: /* We no longer need the private host keys. Clear them now. */
872: if (sensitive_data.nkeys != 0) {
873: for (i = 0; i < sensitive_data.nkeys; i++) {
874: if (sensitive_data.keys[i] != NULL) {
875: /* Destroys contents safely */
876: debug3("clear hostkey %d", i);
877: key_free(sensitive_data.keys[i]);
878: sensitive_data.keys[i] = NULL;
879: }
880: }
881: xfree(sensitive_data.keys);
1.134 markus 882: }
883: for (i = 0; i < options.num_identity_files; i++) {
884: if (options.identity_files[i]) {
885: xfree(options.identity_files[i]);
886: options.identity_files[i] = NULL;
887: }
888: if (options.identity_keys[i]) {
889: key_free(options.identity_keys[i]);
890: options.identity_keys[i] = NULL;
891: }
1.112 markus 892: }
1.31 markus 893:
1.45 markus 894: exit_status = compat20 ? ssh_session2() : ssh_session();
895: packet_close();
1.186 djm 896:
1.312 djm 897: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 898: unlink(options.control_path);
899:
1.353 djm 900: /* Kill ProxyCommand if it is running. */
901: ssh_kill_proxy_command();
1.186 djm 902:
1.45 markus 903: return exit_status;
904: }
905:
1.344 djm 906: static void
907: control_persist_detach(void)
908: {
909: pid_t pid;
1.346 djm 910: int devnull;
1.344 djm 911:
912: debug("%s: backgrounding master process", __func__);
913:
914: /*
915: * master (current process) into the background, and make the
916: * foreground process a client of the backgrounded master.
917: */
918: switch ((pid = fork())) {
919: case -1:
920: fatal("%s: fork: %s", __func__, strerror(errno));
921: case 0:
922: /* Child: master process continues mainloop */
923: break;
924: default:
925: /* Parent: set up mux slave to connect to backgrounded master */
926: debug2("%s: background process is %ld", __func__, (long)pid);
927: stdin_null_flag = ostdin_null_flag;
1.359 djm 928: options.request_tty = orequest_tty;
1.344 djm 929: tty_flag = otty_flag;
930: close(muxserver_sock);
931: muxserver_sock = -1;
1.351 markus 932: options.control_master = SSHCTL_MASTER_NO;
1.344 djm 933: muxclient(options.control_path);
934: /* muxclient() doesn't return on success. */
935: fatal("Failed to connect to new control master");
936: }
1.346 djm 937: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
938: error("%s: open(\"/dev/null\"): %s", __func__,
939: strerror(errno));
940: } else {
941: if (dup2(devnull, STDIN_FILENO) == -1 ||
942: dup2(devnull, STDOUT_FILENO) == -1)
943: error("%s: dup2: %s", __func__, strerror(errno));
944: if (devnull > STDERR_FILENO)
945: close(devnull);
946: }
1.362 djm 947: setproctitle("%s [mux]", options.control_path);
1.344 djm 948: }
949:
950: /* Do fork() after authentication. Used by "ssh -f" */
951: static void
952: fork_postauth(void)
953: {
954: if (need_controlpersist_detach)
955: control_persist_detach();
956: debug("forking to background");
957: fork_after_authentication_flag = 0;
958: if (daemon(1, 1) < 0)
959: fatal("daemon() failed: %.200s", strerror(errno));
960: }
961:
1.315 djm 962: /* Callback for remote forward global requests */
963: static void
964: ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
965: {
966: Forward *rfwd = (Forward *)ctxt;
967:
1.324 djm 968: /* XXX verbose() on failure? */
1.315 djm 969: debug("remote forward %s for: listen %d, connect %s:%d",
970: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
971: rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
1.366 markus 972: if (rfwd->listen_port == 0) {
973: if (type == SSH2_MSG_REQUEST_SUCCESS) {
974: rfwd->allocated_port = packet_get_int();
975: logit("Allocated port %u for remote forward to %s:%d",
976: rfwd->allocated_port,
977: rfwd->connect_host, rfwd->connect_port);
978: channel_update_permitted_opens(rfwd->handle,
979: rfwd->allocated_port);
980: } else {
981: channel_update_permitted_opens(rfwd->handle, -1);
982: }
1.324 djm 983: }
984:
1.315 djm 985: if (type == SSH2_MSG_REQUEST_FAILURE) {
986: if (options.exit_on_forward_failure)
987: fatal("Error: remote port forwarding failed for "
988: "listen port %d", rfwd->listen_port);
989: else
990: logit("Warning: remote port forwarding failed for "
991: "listen port %d", rfwd->listen_port);
992: }
1.318 djm 993: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 994: debug("All remote forwarding requests processed");
1.344 djm 995: if (fork_after_authentication_flag)
996: fork_postauth();
1.318 djm 997: }
1.315 djm 998: }
999:
1.126 itojun 1000: static void
1.331 dtucker 1001: client_cleanup_stdio_fwd(int id, void *arg)
1002: {
1003: debug("stdio forwarding: done");
1004: cleanup_exit(0);
1005: }
1006:
1.368 djm 1007: static void
1008: ssh_init_stdio_forwarding(void)
1.331 dtucker 1009: {
1010: Channel *c;
1.332 djm 1011: int in, out;
1.331 dtucker 1012:
1.368 djm 1013: if (stdio_forward_host == NULL)
1014: return;
1015: if (!compat20)
1016: fatal("stdio forwarding require Protocol 2");
1017:
1018: debug3("%s: %s:%d", __func__, stdio_forward_host, stdio_forward_port);
1.332 djm 1019:
1.368 djm 1020: if ((in = dup(STDIN_FILENO)) < 0 ||
1021: (out = dup(STDOUT_FILENO)) < 0)
1.332 djm 1022: fatal("channel_connect_stdio_fwd: dup() in/out failed");
1.368 djm 1023: if ((c = channel_connect_stdio_fwd(stdio_forward_host,
1024: stdio_forward_port, in, out)) == NULL)
1025: fatal("%s: channel_connect_stdio_fwd failed", __func__);
1.331 dtucker 1026: channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
1027: }
1028:
1029: static void
1.70 markus 1030: ssh_init_forwarding(void)
1031: {
1.86 markus 1032: int success = 0;
1.70 markus 1033: int i;
1.331 dtucker 1034:
1.70 markus 1035: /* Initiate local TCP/IP port forwardings. */
1036: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 1037: debug("Local connections to %.200s:%d forwarded to remote "
1038: "address %.200s:%d",
1.234 deraadt 1039: (options.local_forwards[i].listen_host == NULL) ?
1040: (options.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1041: options.local_forwards[i].listen_host,
1042: options.local_forwards[i].listen_port,
1043: options.local_forwards[i].connect_host,
1044: options.local_forwards[i].connect_port);
1.158 markus 1045: success += channel_setup_local_fwd_listener(
1.232 djm 1046: options.local_forwards[i].listen_host,
1047: options.local_forwards[i].listen_port,
1048: options.local_forwards[i].connect_host,
1049: options.local_forwards[i].connect_port,
1.70 markus 1050: options.gateway_ports);
1051: }
1.283 markus 1052: if (i > 0 && success != i && options.exit_on_forward_failure)
1053: fatal("Could not request local forwarding.");
1.86 markus 1054: if (i > 0 && success == 0)
1055: error("Could not request local forwarding.");
1.70 markus 1056:
1057: /* Initiate remote TCP/IP port forwardings. */
1058: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1059: debug("Remote connections from %.200s:%d forwarded to "
1060: "local address %.200s:%d",
1.248 djm 1061: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1062: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1063: options.remote_forwards[i].listen_port,
1064: options.remote_forwards[i].connect_host,
1065: options.remote_forwards[i].connect_port);
1.366 markus 1066: options.remote_forwards[i].handle =
1067: channel_request_remote_forwarding(
1.232 djm 1068: options.remote_forwards[i].listen_host,
1069: options.remote_forwards[i].listen_port,
1070: options.remote_forwards[i].connect_host,
1.366 markus 1071: options.remote_forwards[i].connect_port);
1072: if (options.remote_forwards[i].handle < 0) {
1.283 markus 1073: if (options.exit_on_forward_failure)
1074: fatal("Could not request remote forwarding.");
1075: else
1076: logit("Warning: Could not request remote "
1077: "forwarding.");
1.366 markus 1078: } else {
1079: client_register_global_confirm(ssh_confirm_remote_forward,
1080: &options.remote_forwards[i]);
1.283 markus 1081: }
1.70 markus 1082: }
1.301 djm 1083:
1084: /* Initiate tunnel forwarding. */
1085: if (options.tun_open != SSH_TUNMODE_NO) {
1086: if (client_request_tun_fwd(options.tun_open,
1087: options.tun_local, options.tun_remote) == -1) {
1088: if (options.exit_on_forward_failure)
1089: fatal("Could not request tunnel forwarding.");
1090: else
1091: error("Could not request tunnel forwarding.");
1092: }
1093: }
1.70 markus 1094: }
1095:
1.126 itojun 1096: static void
1.70 markus 1097: check_agent_present(void)
1098: {
1099: if (options.forward_agent) {
1.254 djm 1100: /* Clear agent forwarding if we don't have an agent. */
1.185 stevesk 1101: if (!ssh_agent_present())
1.70 markus 1102: options.forward_agent = 0;
1103: }
1104: }
1105:
1.126 itojun 1106: static int
1.45 markus 1107: ssh_session(void)
1108: {
1109: int type;
1110: int interactive = 0;
1111: int have_tty = 0;
1112: struct winsize ws;
1113: char *cp;
1.243 djm 1114: const char *display;
1.45 markus 1115:
1.31 markus 1116: /* Enable compression if requested. */
1117: if (options.compression) {
1.316 djm 1118: debug("Requesting compression at level %d.",
1119: options.compression_level);
1.31 markus 1120:
1.316 djm 1121: if (options.compression_level < 1 ||
1122: options.compression_level > 9)
1123: fatal("Compression level must be from 1 (fast) to "
1124: "9 (slow, best).");
1.31 markus 1125:
1126: /* Send the request. */
1127: packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1128: packet_put_int(options.compression_level);
1129: packet_send();
1130: packet_write_wait();
1.156 markus 1131: type = packet_read();
1.31 markus 1132: if (type == SSH_SMSG_SUCCESS)
1133: packet_start_compression(options.compression_level);
1134: else if (type == SSH_SMSG_FAILURE)
1.191 itojun 1135: logit("Warning: Remote host refused compression.");
1.31 markus 1136: else
1.316 djm 1137: packet_disconnect("Protocol error waiting for "
1138: "compression response.");
1.31 markus 1139: }
1140: /* Allocate a pseudo tty if appropriate. */
1141: if (tty_flag) {
1142: debug("Requesting pty.");
1143:
1144: /* Start the packet. */
1145: packet_start(SSH_CMSG_REQUEST_PTY);
1146:
1147: /* Store TERM in the packet. There is no limit on the
1148: length of the string. */
1149: cp = getenv("TERM");
1150: if (!cp)
1151: cp = "";
1.124 markus 1152: packet_put_cstring(cp);
1.31 markus 1153:
1154: /* Store window size in the packet. */
1155: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1156: memset(&ws, 0, sizeof(ws));
1.269 deraadt 1157: packet_put_int((u_int)ws.ws_row);
1158: packet_put_int((u_int)ws.ws_col);
1159: packet_put_int((u_int)ws.ws_xpixel);
1160: packet_put_int((u_int)ws.ws_ypixel);
1.31 markus 1161:
1162: /* Store tty modes in the packet. */
1.115 stevesk 1163: tty_make_modes(fileno(stdin), NULL);
1.31 markus 1164:
1165: /* Send the packet, and wait for it to leave. */
1166: packet_send();
1167: packet_write_wait();
1168:
1169: /* Read response from the server. */
1.156 markus 1170: type = packet_read();
1.43 markus 1171: if (type == SSH_SMSG_SUCCESS) {
1.31 markus 1172: interactive = 1;
1.45 markus 1173: have_tty = 1;
1.43 markus 1174: } else if (type == SSH_SMSG_FAILURE)
1.316 djm 1175: logit("Warning: Remote host failed or refused to "
1176: "allocate a pseudo tty.");
1.31 markus 1177: else
1.316 djm 1178: packet_disconnect("Protocol error waiting for pty "
1179: "request response.");
1.31 markus 1180: }
1181: /* Request X11 forwarding if enabled and DISPLAY is set. */
1.243 djm 1182: display = getenv("DISPLAY");
1183: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1184: char *proto, *data;
1.50 markus 1185: /* Get reasonable local authentication information. */
1.243 djm 1186: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1187: options.forward_x11_trusted,
1188: options.forward_x11_timeout,
1189: &proto, &data);
1.50 markus 1190: /* Request forwarding with authentication spoofing. */
1.316 djm 1191: debug("Requesting X11 forwarding with authentication "
1192: "spoofing.");
1.363 djm 1193: x11_request_forwarding_with_spoofing(0, display, proto,
1194: data, 0);
1.31 markus 1195: /* Read response from the server. */
1.156 markus 1196: type = packet_read();
1.31 markus 1197: if (type == SSH_SMSG_SUCCESS) {
1198: interactive = 1;
1.50 markus 1199: } else if (type == SSH_SMSG_FAILURE) {
1.191 itojun 1200: logit("Warning: Remote host denied X11 forwarding.");
1.50 markus 1201: } else {
1.316 djm 1202: packet_disconnect("Protocol error waiting for X11 "
1203: "forwarding");
1.50 markus 1204: }
1.31 markus 1205: }
1206: /* Tell the packet module whether this is an interactive session. */
1.354 djm 1207: packet_set_interactive(interactive,
1208: options.ip_qos_interactive, options.ip_qos_bulk);
1.31 markus 1209:
1210: /* Request authentication agent forwarding if appropriate. */
1.70 markus 1211: check_agent_present();
1212:
1.31 markus 1213: if (options.forward_agent) {
1214: debug("Requesting authentication agent forwarding.");
1215: auth_request_forwarding();
1216:
1217: /* Read response from the server. */
1.156 markus 1218: type = packet_read();
1.155 markus 1219: packet_check_eom();
1.31 markus 1220: if (type != SSH_SMSG_SUCCESS)
1.191 itojun 1221: logit("Warning: Remote host denied authentication agent forwarding.");
1.31 markus 1222: }
1223:
1.70 markus 1224: /* Initiate port forwardings. */
1.368 djm 1225: ssh_init_stdio_forwarding();
1.70 markus 1226: ssh_init_forwarding();
1.305 dtucker 1227:
1228: /* Execute a local command */
1229: if (options.local_command != NULL &&
1230: options.permit_local_command)
1231: ssh_local_cmd(options.local_command);
1.34 markus 1232:
1.318 djm 1233: /*
1234: * If requested and we are not interested in replies to remote
1235: * forwarding requests, then let ssh continue in the background.
1236: */
1.344 djm 1237: if (fork_after_authentication_flag) {
1238: if (options.exit_on_forward_failure &&
1239: options.num_remote_forwards > 0) {
1240: debug("deferring postauth fork until remote forward "
1241: "confirmation received");
1242: } else
1243: fork_postauth();
1.318 djm 1244: }
1.31 markus 1245:
1.33 markus 1246: /*
1247: * If a command was specified on the command line, execute the
1248: * command now. Otherwise request the server to start a shell.
1249: */
1.31 markus 1250: if (buffer_len(&command) > 0) {
1251: int len = buffer_len(&command);
1252: if (len > 900)
1253: len = 900;
1.316 djm 1254: debug("Sending command: %.*s", len,
1255: (u_char *)buffer_ptr(&command));
1.31 markus 1256: packet_start(SSH_CMSG_EXEC_CMD);
1257: packet_put_string(buffer_ptr(&command), buffer_len(&command));
1258: packet_send();
1259: packet_write_wait();
1260: } else {
1261: debug("Requesting shell.");
1262: packet_start(SSH_CMSG_EXEC_SHELL);
1263: packet_send();
1264: packet_write_wait();
1265: }
1266:
1267: /* Enter the interactive session. */
1.119 stevesk 1268: return client_loop(have_tty, tty_flag ?
1269: options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1.89 markus 1270: }
1271:
1.214 djm 1272: /* request pty/x11/agent/tcpfwd/shell for channel */
1273: static void
1.337 djm 1274: ssh_session2_setup(int id, int success, void *arg)
1.214 djm 1275: {
1.215 djm 1276: extern char **environ;
1.243 djm 1277: const char *display;
1278: int interactive = tty_flag;
1.337 djm 1279:
1280: if (!success)
1281: return; /* No need for error message, channels code sens one */
1.215 djm 1282:
1.248 djm 1283: display = getenv("DISPLAY");
1.243 djm 1284: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1285: char *proto, *data;
1.50 markus 1286: /* Get reasonable local authentication information. */
1.243 djm 1287: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1288: options.forward_x11_trusted,
1289: options.forward_x11_timeout, &proto, &data);
1.50 markus 1290: /* Request forwarding with authentication spoofing. */
1.316 djm 1291: debug("Requesting X11 forwarding with authentication "
1292: "spoofing.");
1.363 djm 1293: x11_request_forwarding_with_spoofing(id, display, proto,
1294: data, 1);
1295: client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN);
1296: /* XXX exit_on_forward_failure */
1.80 markus 1297: interactive = 1;
1.50 markus 1298: }
1299:
1.70 markus 1300: check_agent_present();
1301: if (options.forward_agent) {
1302: debug("Requesting authentication agent forwarding.");
1303: channel_request_start(id, "auth-agent-req@openssh.com", 0);
1304: packet_send();
1.212 djm 1305: }
1.369 dtucker 1306:
1307: /* Tell the packet module whether this is an interactive session. */
1308: packet_set_interactive(interactive,
1309: options.ip_qos_interactive, options.ip_qos_bulk);
1.212 djm 1310:
1.214 djm 1311: client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1.311 djm 1312: NULL, fileno(stdin), &command, environ);
1.45 markus 1313: }
1314:
1.143 markus 1315: /* open new channel for a session */
1.126 itojun 1316: static int
1.143 markus 1317: ssh_session2_open(void)
1.45 markus 1318: {
1.118 markus 1319: Channel *c;
1320: int window, packetmax, in, out, err;
1.60 markus 1321:
1.62 markus 1322: if (stdin_null_flag) {
1.93 itojun 1323: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1324: } else {
1325: in = dup(STDIN_FILENO);
1326: }
1.60 markus 1327: out = dup(STDOUT_FILENO);
1328: err = dup(STDERR_FILENO);
1.45 markus 1329:
1330: if (in < 0 || out < 0 || err < 0)
1.62 markus 1331: fatal("dup() in/out/err failed");
1.45 markus 1332:
1.69 markus 1333: /* enable nonblocking unless tty */
1334: if (!isatty(in))
1335: set_nonblock(in);
1336: if (!isatty(out))
1337: set_nonblock(out);
1338: if (!isatty(err))
1339: set_nonblock(err);
1340:
1.65 markus 1341: window = CHAN_SES_WINDOW_DEFAULT;
1342: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1343: if (tty_flag) {
1344: window >>= 1;
1345: packetmax >>= 1;
1.45 markus 1346: }
1.118 markus 1347: c = channel_new(
1.45 markus 1348: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1349: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1350: "client-session", /*nonblock*/0);
1.45 markus 1351:
1.143 markus 1352: debug3("ssh_session2_open: channel_new: %d", c->self);
1.106 markus 1353:
1.122 markus 1354: channel_send_open(c->self);
1.143 markus 1355: if (!no_shell_flag)
1.310 djm 1356: channel_register_open_confirm(c->self,
1357: ssh_session2_setup, NULL);
1.106 markus 1358:
1.118 markus 1359: return c->self;
1.106 markus 1360: }
1361:
1.126 itojun 1362: static int
1.106 markus 1363: ssh_session2(void)
1364: {
1.143 markus 1365: int id = -1;
1.106 markus 1366:
1367: /* XXX should be pre-session */
1.368 djm 1368: if (!options.control_persist)
1369: ssh_init_stdio_forwarding();
1.106 markus 1370: ssh_init_forwarding();
1371:
1.344 djm 1372: /* Start listening for multiplex clients */
1373: muxserver_listen();
1374:
1375: /*
1.368 djm 1376: * If we are in control persist mode and have a working mux listen
1377: * socket, then prepare to background ourselves and have a foreground
1378: * client attach as a control slave.
1379: * NB. we must save copies of the flags that we override for
1.344 djm 1380: * the backgrounding, since we defer attachment of the slave until
1381: * after the connection is fully established (in particular,
1382: * async rfwd replies have been received for ExitOnForwardFailure).
1383: */
1384: if (options.control_persist && muxserver_sock != -1) {
1385: ostdin_null_flag = stdin_null_flag;
1386: ono_shell_flag = no_shell_flag;
1.359 djm 1387: orequest_tty = options.request_tty;
1.344 djm 1388: otty_flag = tty_flag;
1389: stdin_null_flag = 1;
1390: no_shell_flag = 1;
1391: tty_flag = 0;
1392: if (!fork_after_authentication_flag)
1393: need_controlpersist_detach = 1;
1394: fork_after_authentication_flag = 1;
1395: }
1.368 djm 1396: /*
1397: * ControlPersist mux listen socket setup failed, attempt the
1398: * stdio forward setup that we skipped earlier.
1399: */
1400: if (options.control_persist && muxserver_sock == -1)
1401: ssh_init_stdio_forwarding();
1.344 djm 1402:
1.143 markus 1403: if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1404: id = ssh_session2_open();
1.314 djm 1405:
1406: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1407: if (options.control_master == SSHCTL_MASTER_NO &&
1408: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1409: debug("Requesting no-more-sessions@openssh.com");
1410: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1411: packet_put_cstring("no-more-sessions@openssh.com");
1412: packet_put_char(0);
1413: packet_send();
1414: }
1.255 reyk 1415:
1416: /* Execute a local command */
1417: if (options.local_command != NULL &&
1418: options.permit_local_command)
1419: ssh_local_cmd(options.local_command);
1.301 djm 1420:
1.342 djm 1421: /*
1422: * If requested and we are not interested in replies to remote
1423: * forwarding requests, then let ssh continue in the background.
1424: */
1.344 djm 1425: if (fork_after_authentication_flag) {
1426: if (options.exit_on_forward_failure &&
1427: options.num_remote_forwards > 0) {
1428: debug("deferring postauth fork until remote forward "
1429: "confirmation received");
1430: } else
1431: fork_postauth();
1.318 djm 1432: }
1.327 andreas 1433:
1434: if (options.use_roaming)
1435: request_roaming();
1.31 markus 1436:
1.119 stevesk 1437: return client_loop(tty_flag, tty_flag ?
1438: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1439: }
1440:
1.126 itojun 1441: static void
1.104 markus 1442: load_public_identity_files(void)
1443: {
1.275 djm 1444: char *filename, *cp, thishost[NI_MAXHOST];
1.306 deraadt 1445: char *pwdir = NULL, *pwname = NULL;
1.167 markus 1446: int i = 0;
1.104 markus 1447: Key *public;
1.275 djm 1448: struct passwd *pw;
1.335 djm 1449: u_int n_ids;
1450: char *identity_files[SSH_MAX_IDENTITY_FILES];
1451: Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1.333 markus 1452: #ifdef ENABLE_PKCS11
1.167 markus 1453: Key **keys;
1.333 markus 1454: int nkeys;
1.335 djm 1455: #endif /* PKCS11 */
1.104 markus 1456:
1.335 djm 1457: n_ids = 0;
1458: bzero(identity_files, sizeof(identity_files));
1459: bzero(identity_keys, sizeof(identity_keys));
1460:
1461: #ifdef ENABLE_PKCS11
1.333 markus 1462: if (options.pkcs11_provider != NULL &&
1.167 markus 1463: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 1464: (pkcs11_init(!options.batch_mode) == 0) &&
1465: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1466: &keys)) > 0) {
1467: for (i = 0; i < nkeys; i++) {
1.335 djm 1468: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1469: key_free(keys[i]);
1470: continue;
1471: }
1472: identity_keys[n_ids] = keys[i];
1473: identity_files[n_ids] =
1.333 markus 1474: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 1475: n_ids++;
1.167 markus 1476: }
1477: xfree(keys);
1.127 markus 1478: }
1.333 markus 1479: #endif /* ENABLE_PKCS11 */
1.275 djm 1480: if ((pw = getpwuid(original_real_uid)) == NULL)
1481: fatal("load_public_identity_files: getpwuid failed");
1.307 dtucker 1482: pwname = xstrdup(pw->pw_name);
1483: pwdir = xstrdup(pw->pw_dir);
1.275 djm 1484: if (gethostname(thishost, sizeof(thishost)) == -1)
1485: fatal("load_public_identity_files: gethostname: %s",
1486: strerror(errno));
1.335 djm 1487: for (i = 0; i < options.num_identity_files; i++) {
1.373 ! djm 1488: if (n_ids >= SSH_MAX_IDENTITY_FILES ||
! 1489: strcasecmp(options.identity_files[i], "none") == 0) {
1.335 djm 1490: xfree(options.identity_files[i]);
1491: continue;
1492: }
1.275 djm 1493: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 1494: original_real_uid);
1.306 deraadt 1495: filename = percent_expand(cp, "d", pwdir,
1496: "u", pwname, "l", thishost, "h", host,
1.275 djm 1497: "r", options.user, (char *)NULL);
1498: xfree(cp);
1.131 millert 1499: public = key_load_public(filename, NULL);
1500: debug("identity file %s type %d", filename,
1501: public ? public->type : -1);
1502: xfree(options.identity_files[i]);
1.335 djm 1503: identity_files[n_ids] = filename;
1504: identity_keys[n_ids] = public;
1505:
1506: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
1507: continue;
1508:
1509: /* Try to add the certificate variant too */
1510: xasprintf(&cp, "%s-cert", filename);
1511: public = key_load_public(cp, NULL);
1512: debug("identity file %s type %d", cp,
1513: public ? public->type : -1);
1514: if (public == NULL) {
1515: xfree(cp);
1516: continue;
1517: }
1518: if (!key_is_cert(public)) {
1519: debug("%s: key %s type %s is not a certificate",
1520: __func__, cp, key_type(public));
1521: key_free(public);
1522: xfree(cp);
1523: continue;
1524: }
1525: identity_keys[n_ids] = public;
1526: /* point to the original path, most likely the private key */
1527: identity_files[n_ids] = xstrdup(filename);
1528: n_ids++;
1529: }
1530: options.num_identity_files = n_ids;
1531: memcpy(options.identity_files, identity_files, sizeof(identity_files));
1532: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1533:
1.306 deraadt 1534: bzero(pwname, strlen(pwname));
1.307 dtucker 1535: xfree(pwname);
1.306 deraadt 1536: bzero(pwdir, strlen(pwdir));
1.307 dtucker 1537: xfree(pwdir);
1.214 djm 1538: }
1.352 djm 1539:
1540: static void
1541: main_sigchld_handler(int sig)
1542: {
1543: int save_errno = errno;
1544: pid_t pid;
1545: int status;
1546:
1547: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
1548: (pid < 0 && errno == EINTR))
1549: ;
1550:
1551: signal(sig, main_sigchld_handler);
1552: errno = save_errno;
1553: }
1554:
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